The Navy lost nine ships last week. They were not, however, destroyed in battle or retired. They were instead sacrificed at the political altar of Navy ship counting rules.

As Chris Cavas of Defense News explained, the Obama administration had changed the manner in which it counted ships so it could claim that it was rebuilding the fleet after it hit its low point of 275 during the latter part of the Bush administration. Congress, however, included language in the 2015 National Defense Authorization Act prohibiting the inclusion of patrol coastal vessels the administration had begun counting as part of the fleet in 2014. Consequently, the Navy’s “deployable battle force” shrunk from 284 to 275 ships.

This is hardly a new game and, as Cavas notes, it is largely about politics. Which ships are counted in the fleet total will shift from time-to-time based on the political needs of various constituencies. Sometimes various auxiliaries and support ships are included, for instance, while others are not.

Through World War II, fleets were measured by tonnage. During the Cold War, however, the Soviet Union had a fleet small in tonnage but numerically large, so the number of ships became a convenient basis of comparison for the Navy and its congressional boosters. The debate over ship counts reached its zenith when James Webb, the Vietnam veteran and possible 2016 presidential candidate, resigned as Ronald Reagan’s Navy secretary when it seemed the Navy fleet size would top out at 580 ships instead of the promised 600.[

All of these machinations serve as background for a debate sparked a New York Times opinion piece by Gregg Easterbrook, a contributing editor at The New Republic and The Atlantic. Easterbrook argued that the U.S. Navy is big enough because no other power can match it numerically or challenge its dominance of the world’s oceans. This argument did not sit well with many, and it garnered strong responses from former Navy officer and naval strategist Bryan McGrath at War on the Rocks, and Naval War College Professors James Holmes and Andrew Erickson at RealClearDefense.

Besides correcting some factual errors in Easterbrook’s piece, the crux of the dispute is whether “contesting the ‘blue water,’ or deep oceans” is the Navy’s primary purpose. McGrath, Holmes, and Erickson all suggest that combat in an adversary’s coastal areas and projecting power inland are the Navy’s primary purpose. And all three argue that the Navy is not large enough for this mission.

One of the central issues in this debate is whether we need more aircraft carriers to project power inland, or whether we should rethink our commitment to them given technological developments. While Easterbrook downplays China’s recent development of an anti-ship ballistic missile (ASBM), Holmes suggests that even though it has not yet been tested, the ASBM is being deployed and therefore raises the risks for U.S. aircraft carriers operating near Chinese waters. However, he does not suggest transitioning away from the expensive flattops as the risk to them has increased. And McGrath, for his part, explicitly calls for more carriers.

Not all naval analysts agree. Jerry Hendrix of the Center for a New American security, a retired naval officer who has debated McGrath on the carrier issue, argues that they are simply no longer worth the money. “The queen of the American fleet, and the centerpiece of the most powerful Navy the world has ever seen,” Hendrix wrote in 2013, “is in danger of becoming like the battleships it was originally designed to support: big, expensive, vulnerable—and surprisingly irrelevant to the conflicts of the time.” And Hendrix is hardly alone among naval analysts suggesting a transition away from carriers to less vulnerable undersea capabilities.

The Obama administration’s budget request includes $2.8 billion in acquisition funding for the Ford-class program, a program already beset by cost overruns. If Hendrix and others are correct, they are also of dubious strategic utility. Perhaps focusing on ship type, rather than arbitrary and politically-motivated ship counts, will help steer investments where they are needed most.